Failed Transmission + Warning Lights: Check Cooling System?

Had similar symptoms on my 2015 Chevy Trax diesel last month. The pressure sensor readings were all over the place, triggering multiple warning lights. After leak detection tests, found the transmission oil cooler lines had degraded connection points and were leaking. The cooling system was losing pressure, causing transmission fluid to overheat. Poor cooling efficiency made the transmission act up, rough shifts and grinding were exactly what I experienced. The emergency mode kicks in to prevent severe transmission damage. The radiator repair wasn't the core issue, it was the deteriorated connection between the cooler lines and transmission. Main problem was the wire harness connector to the transmission pressure sensor was corroded, sending faulty signals to the ECU. This is definitely a serious issue that needs immediate attention. Continued driving could cause permanent transmission damage. Would strongly recommend getting a complete pressure gauge diagnostic test done to pinpoint the exact problem, could be sensor related rather than mechanical failure. Key parts replaced during repair: Transmission pressure sensor, Oil cooler line connectors, Wire harness connector, Cooling system pressure tested and recharged

I had those exact same warning lights and transmission problems with my Captiva recently. The mechanic found a coolant leak where the transmission oil cooler connects to the radiator. The pressure gauge readings were way off, which triggered both warning lights. My transmission was slipping and grinding just like yours until they fixed the cooling system issue. The repair involved replacing some corroded connectors and doing a complete coolant system pressure test. Did your mechanic mention what the final repair costs were? Also wondering if you've had any other warning lights pop up since getting it fixed? Mine's been running smoothly for a few months now, but I keep a close eye on the coolant level just to be safe.

The repair ended up being simpler and cheaper than expected, just 95 for fixing a faulty cable connection to the pressure sensor. Once they sorted that out, all warning lights cleared and the transmission's working perfectly now. The pressure gauge readings returned to normal after fixing the defective wiring connector. The cooling system is maintaining proper pressure, and the transmission's shifting smoothly again. No more emergency mode or warning lights in the past few weeks. My case shows how a small electrical issue with the pressure sensor can trigger multiple warning lights and cause transmission symptoms. Getting the proper diagnostic test saved me from unnecessarily replacing major components. The radiator repair was really just about fixing that sensor connection, no actual mechanical problems with the cooling system or transmission. Haven't seen any warning lights since the repair. I still monitor the coolant levels regularly, but everything's been stable. The transmission temperature stays normal even during longer drives now that the pressure sensor is reporting correctly to the ECU.

Thanks for sharing that experience. After all the stress, I finally got my car fixed last week. The mechanic found some corroded connectors between the transmission cooler and radiator coolant lines. The whole diagnostic process with the pressure gauge was actually pretty quick. Total bill came to around 280 Euro, mainly for labor since they had to drain and refill the cooling system after replacing those worn connectors. They also cleaned up the transmission sensor wiring while they were at it. Car's running like new now. No more warning lights or transmission problems. The mechanic showed me how to check the coolant level properly, so I keep an eye on it each week. Transmission shifts smooth as butter these days, such a relief after all that grinding and slipping. Funny how a relatively small cooling system issue can cause so many warning lights and scary transmission symptoms. Really glad I got it checked out before any serious damage happened. The pressure sensor readings are all normal now, and the transmission temperature stays steady even on hot days.